Improvement in piston packing



` @uiten tutes @anni ffice.

'CHARLES H. CLARK, OF WILMINGUYON, DELAWARE.

' Lean-8 Pfam No. 64,491, dna-1M@ 7, 1867,.

IMPROVEMENT IN PISTON PACKING.

@In tlnhnle nfu'tet it iu these tettett ttntt mit making mrt tf tige same.

TO ALL IVI-IOM IT MAY CONGERN Be it known that I, CHARLES II. CLARK, of Wilmington, in the county of New Castle, and State of Delaware, have invented a new and improved- Piston-Packing Ring; and I do hereby declare that the following is a full, clear, and exact descriptionthereof. My object in this invention is to provide a self-adjusting packing for pistons of steam engines, by which l the pressure around the cylinder shall be equalized and the piston maintain a central position without undue pressure on the rubbing surfaces; and theinvention consists in forming the piston-heads and rings with inclined interior surfaces, and with recesses and apertures in and through them, by which the rings are expanded and the piston made steam-tight in the cylinder, and the weight of the piston sustained by steam pressure; and te L enable others skilled in the art to make and use my invention, I will proceed to describe its construction and operation, reference being had to the accompanying drawings, forming part of this specification, and to the L letters of reference marked thereon, in which- Y Figure 1 is a topview of the ring. Figure 2 is a side or edge view. Figure 3 is a vertical section through the line 1. t' of iig. I. s Figures 4 and 5, horizontal section through iig. 2 on the line :n :L:

Figures G and 7, horizontal section through y y of g. 2. Figures 8 and 9, horizontal section through fig. 2 on the line s z. Figure I0 shows the joint-blocks or check-valves. n Y Similar letters of reference indicate like parts. Thegroove which holds the packing-rings is formed around the circumference of the piston-head; it is a cavity having inclined or V-shap'ed sides, with holes or apertures through its lupper and lower as well as through its central or interior surfaces, all of which communicate with the groove before mentioned, and with the packing; mrfl t rings. The piston-head is formed of two pieces, the inclined surface of cach forming the V-shaped groove. A represents the upper piece, and d the lower piece, which form the head, as seen in g. 3. The bright yellow indicates A, und the pale yellow d.A .B and C indicate the two packing-rings D and E, iig. 3, show the spider and follower, which are bolted together, and which confine the piston-head and make the piston complete. The packing-rings B and C are wedge shape with hat faces, which faces come together in the middle of thev V-shaped groove in the head. O'nc ofthe points or edges of the wedge-rings turns up and the other'iturns down from the centre or face, cthe wedge shape itting the inclined surfaces of the groove in the head. These rings are sawed once through the section, which allows them to he expanded by the pressure of steam, as seen at f, fig. 4, and atfg, iig. 2. Where the rings are parted each end has a slot, as seen in figs. 2 and 4. One of the rings C has a recess or groove, 2', in its t'acc, indicated by black marks in figs. 3 and'6. The steam is admitted into thisv recess z' through the saw-parting at f andy of the rings. There are joint-pieces, a and b, shown in fig. 10, which act as check-valves. They lie in the slots in the parted ends of the rings, and admit or confine the steam as the piston may be moving one way or the other. These joint-pieees or valve-blocks have cach a channel on three sides for the steam to pass through, one side of the valve being left smooth, and which closes the aperture when,the steam is admitted into the opposite end of the piston. This closing or opening occurs when the piston changes its direction. The steam is admitted through apertures, one at each end of the piston. The steam enters the recess z' between the rings, and the pressure expands them or throws them apart and on to the inclined surfaces of the head, and against the cylinder. There are holes through the rings which correspond in position with holes through the inclined surfaces of the head or the V-shaped groove, and these holes terminate on 4the r out-side of the piston, and against the interior surface of the cylinder. It is proper that I should here state that this arrangement has reference to a horizontal cylinder, and these lateral holes are for the purpose'ot` allowing the pressure of the steam to impinge against' the sides of the cylinder from the interior of the piston, i and these holes being, as will be observed, on the under side of the piston as it lies in the cylinder, the e'eet will be that the weight of the piston will be borne up by the pressure, the only friction against the cylinder being the expansi ve force of therings. These holes can be multiplied in number to suit the weight of the piston. These lateral holes and the other steam apertures are shown in thehorizontal sectional drawings. Figs. 4 and 5 show the piston-head and rings A taken o' and B left; figs. 6 and 7 with B taken offend C left, and figs. S and 9 with C taken ofi', leaving d. The recess 2' is shown in fig. G by the shaded portion. fis the aperture tondmit steam to the recess on one side of lthe piston, and g on the other side. The snm-l1 valve-blocks a :ind fig. 10, are placed in the slots atfnnd g. When the piston es it stands in fig. 3 is moving up, the steam pressure beingon the bot-tom of the pist-on, the steam will lift the little valveblock from the holeg in the bottom of the head, and passing round the grooved side of the block, will enter the recess z'in the ring` c, from which it has access to the chamber in the interior of the piston. There is nou' an equilibrium in the pressure in the cylinder below the piston and throughout the interior of the piston, and the pressure forces up the other valve-block, which closes the holefthrough the upper side, thus confining the stea'm and preventingjI its escape to the upper portion of the cylinder.

Having thus described my invention, what I claim as new, :1nd desire to secure by Let-ters Patent, is-

1. The packing-rings B and C, of wedge-shaped form, with the recess z' between their faces, and with the srnv-pa1-ted and slotted ends in combination with a piston. Y

2. The valves a and b, in combination with the packing-rings and the apertures through the piston-head, substantially as described.

CHARLES H. CLARK.

Witnesses:

WILLIAM H. MooNEY, H. A. SAUNDERS. 

